The present invention generally relates generally to the fields of tinted lenses and methods of manufacture.
Tinted contact lenses have steadily gained in popularity since their introduction into the marketplace. In particular, colored contact lenses that include images that mimic the iris of an eye are particularly popular. However, colored contact lenses made by traditional technologies suffer from poor image quality and other difficulties, including leaching of pigments present on the surface of lenses, unnatural appearances, fading of colors and limited number of colors to choose from. The present invention addresses these problems, and provides additional and related benefits as well.
A variety of colored contact lenses and methods of making them have been described. For example, U.S. Pat. No. 5,018,849 to Su et al., issued May 28, 1991, describes colored contact lenses that form a laminated structure whereby a pigment is provided on the top layer of the contact lens and opaque material is sandwiched between two layers of the contact lens material, such as polymers. The opaque material blocks the natural color of the wearer""s iris, and the pigment gives the wearer""s eye the appearance of a desired color. These contact lenses have the undesirable quality of looking unnatural due to the limited number of colors that are available. In addition, during manufacture the opaque material and pigment are applied to the contact lens material in a plurality of steps, using one color per step.
In U.S. Pat. No. 5,034,166 to Rawlings et al., issued Jul. 23, 1991, non-laminated colored contact lenses are described. The pigment in this type of colored contact lens is casted into the structure of the lens material. The pigment is dispensed one color at a time during lens manufacturing which limits the number of colors that can be used to make colored contact lenses. The resulting colored contact lens is undesirable because the wearer""s eyes appear unnatural. Furthermore, the pattern and pigments used in this method is limited which results in an unnatural looking contact lens. Also, existing methods provide customers with limited choices of colors and patters and the lenses produced by these methods can provide pigments on the a surface of a lens, which can make the lenses uncomfortable for the wearer and prone to fading of the pigment.
The colored contact lenses described in U.S. Pat. No. 5,106,182 to Briggs et al., issued Apr. 21, 1992, described a laminated colored contact lens. In this contact lens, pigmentation is provided on one portion of a contact lens using a pad transfer method using a rubber stamp having raised radial segments. The pad transfer method applies pigment to the portion of the contact lens to form a crude pattern. The pad is then pressed to the portion of the contact lens to smear the pigment and the pad disengaged from the portion of a contact lens. The lens is rotated, and the process is repeated as desired. The resulting colored contact lens is undesirable because of the limited number of colors that can be used and the resulting pigmentation pattern has an unpredictable and unnatural appearance.
U.S. Pat. No. 5,160,463 to Evans et al., issued Nov. 3, 1992, describes a colored contact lens made by applying a first pigment in a first pattern to a molding device. Additional pigments in additional patterns can be applied to the molding device in independent applications. The resulting image on the molding device can be transferred to a contact lens. The use of multiple printing steps is undesirable due to the increased number of applications that are needed to create an image. In addition, this method results in an image of unnatural appearance due to the limited number of colors that can be used to create the image.
Colored contact lenses reported in U.S. Pat. No. 5,414,477 to Jahnke, issued May 9, 1995, relate to images that are made using pad transfer methods to form a plurality of dots of unnatural appearance. A plurality of printing processed can be used to create an image comprising more than one color that reportedly results in an image with a more natural appearance. These dots are of relatively definite in shape and relatively large in size and thus have an unnatural appearance. The colored contact lenses made using these methods also have a limited number of colors and patterns that can be used, which results in an unnatural looking product.
The present invention addresses the problems associated with described tinted contact lenses by providing an image on or within a contact lens that is of superior quality. The increased quality of the image results in a tinted contact lens that has a natural appearance.